Hydrocarbon fluids, e.g. oil and natural gas, are obtained from a subterranean geologic formation, referred to as a reservoir, by drilling a well that penetrates the hydrocarbon-bearing formation. Once a wellbore is drilled, various forms of well completion components may be installed to control and enhance the efficiency of producing fluids from the reservoir. In some applications, for example, a formation isolation valve (FIV) may be used to isolate the formation or portions of the formation. Such a valve may be run in a sand face completion.
Formation isolation valves generally are actuated to a closed position with a shifting tool after run-in of a sand face completion and then opened through a subsequent operation, e.g. an intervention operation. In some applications the subsequent operation may be an interventionless operation, but existing interventionless operations are relatively time-consuming and expensive. For example, certain existing systems enable opening of the formation isolation valve via tubing pressure cycles with liquid in the tubing. Generally, the density of the fluid above the closed valve is such that the hydrostatic pressure of the fluid column above the closed valve is lower than the formation pressure below the valve. This is done to allow the information to flow naturally after the valve is opened to put the well on production. However, in a well drilled and completed in a depleted formation the formation pressure below the valve may be lower than the hydrostatic pressure from the fluid column above the valve. To allow the well to start production in this type of situation, the fluid column above the closed valve is displaced partially or fully with nitrogen gas. After the valve is opened, the gas pressure is bled off to reduce the pressure to a level below the formation pressure so the well can start flowing. However, the nitrogen in the tubing can inhibit the effectiveness of the cycles and also can require substantial amounts of time to open the formation isolation valve.